Efficacy of Clindamycin Hydrochloride in Refractory Periodontitis: 12-Month Results.

The purpose of this study was to evaluate the use of Clindamycin hydrochloride as an adjunct to conventional periodontal therapy in the treatment of patients who had previously been unsuccessfully treated with scaling, periodontal surgery and the use of tetracycline. Thirteen patients with a history of "refractory" periodontitis were thoroughly scaled and monitored by repeated attachment level measurements for the presence of active destructive periodontitis. Disease activity was defined as a 3-mm loss in attachment from baseline measurements or the occurrence of a periodontal abscess. When active disease was detected, each patient was scaled again and placed on Clindamycin hydrochloride 150 mg qid for 7 days. Following the adjunctive use of Clindamycin in combination with scaling, the incidence of gingival sites demonstrating active disease in the group of 13 patients decreased from an annual rate of 10.7 to 0.5%. Each patient demonstrated a decreased incidence of active sites per unit of time. Clinical parameters such as probing depth, gingival redness, bleeding on probing and suppuration showed dramatic improvement at 12 months after Clindamycin therapy. The percentage of pockets with probing depths greater than 6 mm, 4 to 6 mm and 1 to 3 mm changed from 11 to 2%, 38 to 24% and 51 to 74% respectively, following Clindamycin therapy as compared to scaling alone. The percentage of sites bleeding on probing decreased from 33% after scaling alone to 8% following Clindamycin and scaling. Gingival redness decreased from 36 to 1% of sites. Suppuration also decreased from 8% of buccal or lingual surfaces after scaling alone to 1% of surfaces following scaling and Clindamycin. Clindamycin treatment resulted in a significant change in the microbial flora as demonstrated by darkfield microscopy. Prior to Clindamycin therapy, active sites averaged 35% spirochetes, 23% motile rods, 38% nonmotile rods and 4% coccoid cells. At 12 months postclindamycin treatment, spirochetes averaged 8%, motile rods 6%, nonmotile rods 57% and coccoid cells 28% of the organisms present. Our findings indicate that Clindamycin is useful as a treatment modality in cases which do not respond to conventional treatment methods. Due to possible adverse side effects, Clindamycin should be reserved for those patients for whom treatment modalities of lesser risk have been unsuccessful and in whom the subgingival flora is susceptible to this agent.